burgers_diffusion_error.cc

The diffusive Burgers equation – error analysis

#include "rheolef.h"
using namespace rheolef;
using namespace std;
#include "burgers_diffusion_exact.h"
int main(int argc, char**argv) {
environment rheolef (argc, argv);
Float err_expected = (argc > 1) ? atof(argv[1]) : 1;
Float epsilon;
din >> catchmark("epsilon") >> epsilon;
branch even("t","u");
Float t=0; field uh;
Float err_linf_l2 = 0,
err_l2_l2 = 0,
err_linf_linf = 0,
meas_omega = 0;
size_t n = 0;
bool have_meas_omega = false;
dout << "# t err_l2(t) err_linf(t)" << endl;
while (din >> even(t,uh)) {
const geo& omega = uh.get_geo();
if (!have_meas_omega) {
meas_omega = integrate(omega);
have_meas_omega = true;
}
integrate_option iopt;
iopt.set_order (2*uh.get_space().degree()+1);
field pi_h_u = interpolate (uh.get_space(), u_exact(epsilon,t));
Float err_linf = field(uh - pi_h_u).max_abs();
Float err_l2 = sqrt(integrate (omega, sqr(uh - u_exact(epsilon,t)), iopt)/meas_omega);
err_linf_linf = max(err_linf_linf, err_linf);
err_linf_l2 = max(err_linf_l2, err_l2);
err_l2_l2 += sqr(err_l2);
dout << t << " " << err_l2 << " " << err_linf << endl;
++n;
}
err_l2_l2 = sqrt(err_l2_l2/n);
dout << "# err_l2_l2 = " << err_l2_l2 << endl
<< "# err_linf_l2 = " << err_linf_l2 << endl
<< "# err_linf_linf = " << err_linf_linf << endl;
return (err_linf_l2 <= err_expected) ? 0 : 1;
}
main
int main(int argc, char **argv)
Definition: burgers_diffusion_error.cc:29
burgers_diffusion_exact.h
The diffusive Burgers equation – its exact solution.
Float
see the Float page for the full documentation
branch
see the branch page for the full documentation
field
see the field page for the full documentation
geo
see the geo page for the full documentation
rheolef::din
idiststream din
see the diststream page for the full documentation
Definition: diststream.h:427
rheolef::dout
odiststream dout(cout)
see the diststream page for the full documentation
Definition: diststream.h:430
rheolef::field
field_basic< Float > field
see the field page for the full documentation
Definition: field.h:419
mkgeo_ball.n
int n
Definition: mkgeo_ball.sh:150
rheolef
This file is part of Rheolef.
Definition: compiler_eigen.h:37
rheolef::integrate
std::enable_if< details::is_field_expr_v2_nonlinear_arg< Expr >::value &&! is_undeterminated< Result >::value, Result >::type integrate(const geo_basic< T, M > &omega, const Expr &expr, const integrate_option &iopt, Result dummy=Result())
see the integrate page for the full documentation
Definition: integrate.h:202
rheolef::interpolate
field_basic< T, M > interpolate(const space_basic< T, M > &V2h, const field_basic< T, M > &u1h)
see the interpolate page for the full documentation
Definition: interpolate.cc:233
rheolef.h
rheolef - reference manual
u_exact
Definition: interpolate_RTk_polynom.icc:125
u_exact
g u_exact
Definition: taylor_exact.h:26
epsilon
Float epsilon
Definition: transmission_error.cc:25